1. Field of the Invention
This invention relates to gas chromatographs, and more specifically to thermostatic control for a microvalve assembly and associated components of a gas chromatograph or similar instrument.
2. Description of the Prior Art
The gas chromatograph (see U.S. Pat. No. 4,474,889, incorporated by reference) is well-known in the art. A gas chromatograph has three main components: an analytical column which separates physically the components of a sample mixture, a detector to sense the individual components after separation, and an injector to introduce an amount of the sample into the analytical column for separation. Chemicals present in the sample can adhere to components of the gas chromatograph, and thereby degrade or limit the performance of the gas chromatograph.
It is known in the art to heat the analytical column to prevent the chemicals from adhering. It is known in the art to heat the other components of the gas chromatograph system to prevent the adhesion of chemicals therein. Problematically, these other methods are indirect, utilize bulky heating elements and hence consume large amounts of power. For a portable or battery-operated gas chromatograph, less bulky and energy efficient heaters are especially desirable.
Therefore, there is a need for compact, energy-efficient, battery-operable heating for gas chromatograph components to prevent chemicals in the sample from adhering undesirably to the components.